Entrainment gearing for booster motors



April 13 1926. 1,580,838

J. A. McGRi-:w

ENTRAINMENT GEARING FOR BOOSTER MOTORS Original Filed March 25. 1924 2 Sheets-Sheet 1 INVENTOR BYE M ATTRNEx/f April 13 1926.

J. A. MCGREW ENTRAINMENT GEARINO FOR BOOSTER MOTORS Original Filed March 25, 1924 2 Sheets-Sheet 2 Patented Apr. 13, 1926.

UNITED STATES PATENT OFFICE.

JOHN A, MGGREW, 0F ALBAN?, NEW YORK.

ENTRAINMENT GEARING FOR BOOSTER MOTORS.

Application led March 25, 1924, Serial No. 701,660. Renewed September 19,y 1925.

To all whom t may concern:

Be it known that I, JOHN A. MoGEEw, a citizen of the United States, and a resident of Albany, county of Albany, and Stateof New YOrlQ'have invented certain new and useful Improvements in Entrainment Gearing for Booster' Motors, of Awhich the following is a specification.

This invention relates to entrainment gearing for booster Motors, such as are used for aiding ork supplementing the main engine of a locomotive in propelling atrain at low speeds. A booster motor of this type and particularly designed for use in connection with one of the tender trucks of a locomotive is shown and described in Patent 1,412,250, issuedApril 11, 1922, to John A. McGrew and .lames T. Lores. Also in a second Patent 1,447,352, issued to the same inventors on March 6, 1923, there is shown and described an ventrainment mechanism for such a booster motor, wherebyl a shaft driven by the motor may be thrown into gear with a 'normally idle axle of the truck. Such entrainment mechanism includes a rocker member carrying an idler gear, and this member is mounted for rock-ing or oscillating movement directly upon the motor driven shaft. In operation it has been found that when the rocker member is actuated so as tohold the idler gear in mesh with a fixed gear on the truck axle the excessive friction between the rocker member and the rotating driven shaft causes the oil bath in which the gear elements run to become very highly heated to such an extent, in fact, that there is danger of the oil being ignited.

It is the primary object and purpose of my present improvements to `provide means whereby the above noted difliculty will be obviated. To this end in one embodiment of the invention I provide an independent mounting forA the rocker member at the same time insuring the oscillating or rocking movement of said member about an axis which is precisely coincident with the axis of the motor driven shaft, so that the idler gear in its planetary movement traverses a path which throughout its length is always concentric with the driven shaft, whereby the full and complete meshing of the teeth of the idler gear with the teeth of the gear on said driven shaft will be at all times maintained.

In my present disclosure I have illustrated a practical form of this improvement, which consists in providing spaced bearing pedestals for the` driving shaft on the motor carrying frame, and providing these pedestals with extensions concentric with the driving shaft at opposite sides of the gear .fixed upon said shaft. The rocker member 1s formed with spaced parts between which the idler gear is journaled, the said parts straddling the gear on the driving shaft, and being loosely mounted for free oscillating4 or rocking movement nponk the extensions of the bearing pedestals. Thus it will be apparent that, by mounting the rocker mem ber in this manner, its axis of oscillation will, be coincident with the shaft axis, while atfthel same time the rotating .shaft is relieved of all frictional pressure of the rocker member thereon. y

It is 'a further general object of the in-v vention to improve the entrainment means shown inthe patent lastl referred to in the particulars just described without complieating the construction, or lmaterially in. creasing the cost of production.

With the above and other objects in view, the inventionconsists in the improved entrainment mechanism for booster niotors, and more particularly'in the mounting and arrangingl of the several parts thereof, as will be hereinafter more fully described,

illustrated in the accompanying drawings,

and subsequently incorporated in thesubjoined claims.

In the drawings wherein I have illustrated one simpleand satisfactory embodiment of the invention, andin which similar yreference characters designate corresponding parts through the several views :r q

Figure 1 is a fragmentary p'lanview of a booster motor having an entrainment mechanism embodying my present improvements.

Figure 2 isa sectional' view taken on the line 2-2 ofFigure 1.

Figure 3 is an enlarged sectional view taken on the line 3-3 of Figure 2.

In the accompanying drawings I have illustrated only so much of the motor and its mounting with relation to the axle it is to drive as is necessary to a clear understanding of the present invention, and for the purposes of this explanation it will suffice to state that the several parts of th'e motor are carried by a frame, 5, which may be substantially of the construction disclosed in a co-pending application of John A. Mc- Grew and James T. Loree, filed May 6, 1923, Serial Number 637324. This motor carrying frame has a three point bearing suspensionbetween and upon the spaced axles of the truck, substantially in the manner shown in the patent first above referred to. In the accompanying drawings I have shown only one truck axle, 6, with which the motor is to be operatively connected by means of the entrainment mechanism.

In Figure 2 of the drawings the steam supply pipe, 7, which supplies live steam from the main locomotive power plant to the cylinders of the booster motor is shown, and there is interposed in this supply pipe a piston valve 8, actuated by the pressure of the steam passing through said pipe. The movable element of this valve is connected by the rod 9 to the idler gear carrying member of the entrainment mechanism, which I shall presently describe in detail.

The driving shaft, 10, for the truck axle, 6, is arranged in spaced parallel relation to said axle, and rotatably supported in the spaced bearing pedestals 11, which are integrally formed with the base plate of the frame 5. The opposite ends of this shaft 10 have suitable driving connections with the reciprocating pistons'of the booster motor, and a removable cap 12 is associated with each of the pedestals 11. The shaft 10 turns in bronze metal bushings 13, mounted upon each of the said pedestals, suitable provision being made in these bushings and the bearing caps 12 for the application of lubricating oil to the inner sides of the bearing bushings and upon the driving shaft.

The pedestals 11 on the inner sides thereof and at their upper ends and the bearing caps 12 are formed with mating semi-cylindrical extensions 14; the bushings 13 extending from the outer sides of the bearing pedestals to the extremities of said extensions. Between these extensions 14 of the shaft bearings the driving gear 15 is fixed upon said shaft. A relatively large gear 16 is secured upon the truck axle 6, and power is transmitted from the shaft 10 to the axle 6 through the medium of gear element 17, which is movable into and out of meshing engagement with the fixed gear on the-truck axle.

The gear element 17 is mounted and supported for planetary movement with respect to the driving gear 10 in a rocker member 18. This rocker member has complementary spaced parts 19 integrally connected with each other by the web 20. Each of these parts 19 of the rocker is provided with a bearing portion 21, which is loosely engaged upon the extensions 14 of the spaced bearings for the driving shaft 10. The gear 17 is loosely journaled upon a fixed axis 22, mounted in the spaced portions 1S) of the rocker, with the teeth of said idler gear constantly in full mesh with the teeth of the driving gear 15. The web 2O is provided with spaced arms 23, to which the upper end of the valve rod 9 is pivotally connected. This entrainment gear together with the fixed gear 1G on the truck axle operates in a suitable lubricating oil contained in the housing 24 which encloses the gear parts and the rocker member. The bearing portions 21 of the rocker member are provided with suitable oil feed ducts 25, whereby oil will be constantly supplied to the inner faces of said bearing portions and the outer faces of the extensions 14 of the main driving shaft bearings upon which the rocker is mounted.

From the foregoing it will be evident thatl the rocker membercarrying the idler gear may freely rock or oscillate upon the bearing extensions 14 at opposite sides of the driving gear 15, and that the axis of oscillation of t-his rocker member exactly coincides with the axis of the driving shaft, so that the teeth of the idler gear and t-he teeth of the driving gear 10 will always be maintained in full intermeshing relation with each other during the planetary movement of the idler gear. It will, of course, be understood that normally, or when no steam is passing through the supply pipe 7, the idler gear is out of mesh with the gear 1G on the truck axle. When, however, steam is supplied to the booster motor cylinders, such steam, before entering the cylinders, acts against the valve 8, moving the same against the spring pressure, so as to rock or oscillate the member 18 carrying the gear 17, and thereby throw said gear into meshed relation with the fixed gear on the truck axle. The manner in which this intermeshing action between the gear elements is automatically controlled with relation to the operation of the booster motor is fully explained in the McGrew and Loree Patent 1,447,352, above referred to, and therefore need not here be further described. It is of importance to note that, by reason of my present improvement, the upward stress of the rocker member, as it constantly urges the idler gear into mesh with the gear on the truck axle under the pressure of steam against the valve piston is borne by the stationary bearing extensions 14, whereas in thel 12o arrangement shown in said patent, this pressure is exerted against the rotating driving shaft. The resistance Which Was thus offered to the rotation of the driving shaft produced very high friction, so that thev oil was heated to a temperature dangerously near to the ignition point. The possibility of overheating' the lubricating oil bath is entirely precluded in my new mounting` and arrangement of this rocker member, vvhich arrangement also more reliably assures the planetary movement of the idler gear in a path Which will be always exactly vconcentric with the driving shaft, so that there Will be no radial shifting of the teeth of the idler gear with respect to the teeth of the driving gear, and thereby insuring the transmission at all times of the full power output of the motor to the truck axle, Without liability of mutilating the gear teeth.

From the foregoing description, considered in connection with the accompanying drawings, the construction, manner of operation and several advantages of my present improvement Will be clearly understood. It will be seen that in a very simple manner, which does not involve a great departure from the original type of entrainment mechanism, as shovvn in said issued patent, I have succeeded in appreciably increasing the efficiency and serviceable operation of such mechanism, relieving the parts thereof of excessive Wear and obtaining a more positive and exact functional action of the elements, while eliminating all danger from overheating of the lubricant. I have herein particularly described and illustrated a mounting and arrangement of the rocker member for the idler gear which has been ll i) found to give highly satisfactory results in practice. Nevertheless, the possibility that the essential features of my present disclolsure might be exemplified iny other alterna tive structures Will be readily appreciated, and it is therefore to be understood that I reserve the privilege of adopting all such legitimate changes in the form, construction and relative arrangement of the several parte as may be fairly embodied Within the spirit and scope of the invention as claimed.

(ll-aims:

l. In combination with an axle and motor actuated driving shaft therefor, means for connecting and disconnecting said shaftto and from the axis, comprising gear elements fixed to said shaft and axle respectively, and a gear element in constant mesh with the gear element on said shaft, and bodily movable in a planetary path into and out of engagement With the gear on said axle, a rocker member supporting the latter gear element, and a means for mounting said rocker member for movement about an axis coinciding with the axis of said driving' shaft but free of bearing contact upon said shaft.

12. In' combination With 'anfaxle and motor actuated driving shaft therefor, 'and a bearing for said driving shaft, means for connecting andl disconnecting said shaft to and from the axle, comprising gear elements fixed to said shaft and axle respectively, a gear element in constant mesh With the gear element on said shaft, and'bodily movable in a planetary path into and out of engagement With the gear on said axle, and a rocker member oscillatably mounted upon the drivA ing shaft bearing, supporting the latter gear element for movement in a planetary path and in constant concentric relation to the driving shaft. l

3. In combination With an axle and motor actuated driving shaft therefor, Vmeans for connecting and disconnecting said shaft to and from the axle, comprising gear elements fixed to said shaft and axle respectively, a gear element in constant mesh With the gear element on said shaft, and bodily movable in a planetary path into and out of engagement vvith the gear on said axle, an oscillatable support for the latter gear element, and an independent bearing concentric to the driving shaft upon Which said support is mounted to oscillate about an axis coinciding with the axis of said driving shaft.

4. In combination With an axle and motor actuated driving shaft, spaced bearings for said driving shaft, means for connecting and disconnecting said shaft to and from the axle, comprising gear elements fixed to said shaft and axle respectively, and a gear ele ment in constant mesh With the gear clement on said shaft, and bodily movable in a planetary path into and out of engagement With the gear on said axle, and a rocker member straddling the gear on the driving shaft. and mounted upon said spaced shaft bearings, said rocker member supporting the latter gear element and oscillating upon said bearings about an axis coinciding vvith the axis of said driving shaft.

5. In combination With an axle and motor actuated driving shaft therefor, means for connecting and disconnecting said shaft to and from the axle, comprising gear elements fixed to said shaft and axle respectively, a bearing for the driving shaft at each side of the gear element thereon, said bearings having longitudinal extensions on their inner sides opposed to the gear element, a rocker member straddling the gear clement on said shaft, and having spaced parts mounted upon the respective bearing extensions for rocking movement about an `axis coinciding with the axis of said driving shaft, and an idler gear element journaled in said rocker member in constant mesh With the gear element on the driving shaft, and movable With the rockerinember in a planetary path into and out of meshing engagement with the gear element on said axle.

to the axle, an oseillatable support ifor the latter gear element, and a common hearing 10 for said driving shaft and said support.

In testimony that I claim the foregoing as my inventionr` I have signed my name hereto.

JOHN A. MCGREW. 

